Our objective is to understand the mechanisms by which genes are read out and controlled. We plan to characterize the detailed interaction of the lactose repressor and the CAP protein with DNA by experiments which reveal which phosphates these proteins touch when they bind to DNA, and to characterize promoters for the RNA polymerase by determining which bases are critical for that interaction using experiments which modify DNA with dimethylsulfate or with hydrazine. We plan to crystallize the lac repressor, and to do an X-ray structure analysis of that protein and of its complex with DNA. We plan to extend our new chemical method of DNA sequencing to sequence 150 to 200 bases of DNA directly. We plan to use the new sequencing methods to sequence the lactose i gene, the i gene promoter, and complete the sequencing of the three T7 early promoters, and to sequence the initial regions of the reverse transcript product of various RNA tumor viruses. We intend to make poly-operator and poly-promoter plasmids which will yield very large amounts of specified sequences containing the lac operator or the lac operator and promoter, multi-milligram amounts. We plan to make plasmids which will transcribe eucaryotic structural genes under the transcription control of the lac promoter, to produce large amounts of eucatryotic proteins in bacterial cells.